Biology
During ventricular systole, the atrioventricular valves (P) …………… and semilunar valves (Q) …………… .
- P-close, Q-open
- P-close, Q-close
- P-open, Q-close
- P-open, Q-open
Circulatory System
ICSE Sp 2025
24 Likes
Answer
P-close, Q-open
Reason — The atrioventricular valves close to prevent the backflow of blood into the atria, and the semilunar valves open to allow blood to be pumped into the pulmonary artery and aorta.
Answered By
13 Likes
Related Questions
The antiseptic present in tears:
- Iodine
- Hydrogen peroxide
- Lysozyme
- Lysosome
Assertion (A) : The foetus respires but does not breathe.
Reason (R): The maternal blood supplies oxygen to the foetus through placenta.
- A is True and R is False
- A is False and R is True
- Both A and R are True
- Both A and R are False
The two cerebral hemispheres are joined by a sheet of fibres called:
- Pons
- Corpus luteum
- Hypothalamus
- Corpus callosum
The onset of menstruation in a human female is called:
- Menopause
- Menarche
- Ovulation
- Oogenesis